What's With The LDH Hose, Westchester?

[x635 4,066]

So, I've been driving through some fire districts over the past few months, and I've been noticed 1/2 to 1/4 filled LDH hose beds.

Some of these departments have areas where they need to relay pump, especially up hills, and others have had water issues and have potential water issues. So why skimp on hose? Great hydrant system? What about in a disaster or water distribution problems? Incident on a major highway? One apparatus can't be expected to carry all the LDH for logistical reasons.

Other then "that's too much to pack and test", why not fill a bed with LDH? I was thinking weight issues, since some of the departments have floor problems, but still. I was in a volunteer department that carried a lot of LDH, but we had areas of our district and mutual aid districts where it was absolutely needed despite hydrants. Heck, departments used to special call us for it. It was a great insurance policy.

Maybe I'm just out of the modern loop, and there really isn't a need for LDH in an urban hydranted district.

Here's an example. (Blurred to protect department's identity). I'm not trying to pick on anyone, but just curious, and need to use a visual example:

[dc2t 80]

Once we got rid of the buckets and went to LDH, the hose load was figured for the longest hose lay.

[x635 4,066]

Once we got rid of the buckets and went to LDH, the hose load was figured for the longest hose lay.

But how do you really determine that? Isn't it better to have more then not enough? I'm honestly asking, not telling.

[STAT213 332]

Well, when you do your friction loss calcs, you figure out how much IS enough. You simply can't pump and endless stretch. . A thousand feet of four inch and a 1500 GPM pump get you right at 1000 gallons a minute before you start to fall off the curve, and become inefficient. So...we carry 1000 feet, and that is enough for that one pump. And, if you're doing relay pumping, you're probably beyond the point of mattering in terms of outcome. I haven't done the math for five inch, but its easy enough to do if you want to take the time.

Additionally, hose ain't cheap.

And, if you spec the tank at 500 or 750 gallons, you have the luxury of room in your bed, so it stays nice and low.

My thoughts, anyway.

[PFDRes47cue 653]

My department won't give my rig anymore... Stuck at 300 feet with a 2000 gpm pump.

[Bnechis 3,961]

A thousand feet of four inch and a 1500 GPM pump get you right at 1000 gallons a minute before you start to fall off the curve, and become inefficient. So...we carry 1000 feet, and that is enough for that one pump. Additionally, hose ain't cheap.

If the cost of hose is an issue why spend the $$$ on a 1500gpm pump when the maximum amount of water you can move is 1,000gpm. You can go smaller pump, smaller engine and drive train, shorter more manuverable etc.

[Bnechis 3,961]

My department won't give my rig anymore... Stuck at 300 feet with a 2000 gpm pump.

Damn the standard scotty, full speed ahead.

But I'm giving it all she's got jim.......

[x635 4,066]

My statements are based off of not everyday fires, but big fire, big water type of fires.

Well, if the first or second due lays in, and they don't have enough hose, or a main fails and they have to stretch to another hydrant, then what? Once ladders and rescues and chiefs cars stage wherever they want, it is quite difficult to stretch more LDH in. If people are buying 2,000 GPM pumpers, then they should be able to able to input and output 2,000 gpm and have the hose to do it with. And I thought relay pumping friction loss went down to 0 each time it hit the next engines pump?

So, if New Rochelle's water mains go down, as we've seen in other surrounding cities over the past few years, let's say for this story near the New Rochelle Mall, at the height of traffic, would it be easier for a tanker shuttle or to pump water from the Long Island Sound up? Yonkers, in the tree streets, hydrant system sucks up there, wouldn't a stretch of LDH be easier?

So, flip side of the question. For a rural department with limited to no hydrants, and long stretches due to narrow roads and driveways, is this too much LDH? Keep in mind this is on a water supply engine, not a city service or suppresion engine.

And for those true FDNY buffs, let's not forget the "Super Pumper" concept. Or the Philadelphia "Pipeline" concept. Or, in modern day, the NJ Neptune High flow 6" system they have in place.

[mreis95 77]

Well if they took hose off the above engine wouldn't that make it this 1/2 the hose bed scenario like you said in your first post? In your opinion what do you think is the proper amount of LDH for an Engine to carry?

[SageVigiles 1,194]

For the department's that have the luxury of a "water supply engine" that's a great idea. But not everybody has that. It would be great to have a nice low bed of 5" hose, but if you need the tank capacity in case you're first due and all alone, then what choice do you really have?

If you're doing relay pumping, by definition you aren't doing it alone. That means you have multiple hosebeds to put to use for the stretch. But if you calculate your furthest stretch from a water source, why would you need to carry much more hose than would fit on it? Sure, keep some extra on the rig for unforeseen circumstances, but at a certain point you pass the threshold of "prepared" to the point of "unnecessary." Seems wasteful to expose all that hose to the elements if you aren't realistically going to use it.

Also, NJ's Neptune system has 12" LDH. But that's beyond what 98% of us are ever going to face, that's for a catastrophic fire scenario or a total shutdown of water supply systems to an entire region. Think of the high hazard occupancies mid/northern Jersey has to face, chemical refineries, storage tanks, massive railyards with every kind of methyl-ethyl-bad-stuff, the list goes on. It makes total sense why they'd plan and equip for something like this, the event probability is high and so is the impact probability. Why would Westchester or most of CT need that kind of system? We simply do not have that kind of industry on that kind of scale.

[FF1 172]

Seth,

My FD has 100 ft more than the longest stretch in our response area. We roll 2 Engines to full alarms, so even with a bad hydrant, we would be able to relay pump with no issue whatsoever

[x635 4,066]

Well if they took hose off the above engine wouldn't that make it this 1/2 the hose bed scenario like you said in your first post? In your opinion what do you think is the proper amount of LDH for an Engine to carry?

Whatever the district's governors feel that is neccesary, in line with what standards and guidelines reccomend. I'm just enjoying discussing different people views and insights on one of the most important, essential tools we carry and how much of it that we do.

I do feel, that, in today's world, never say never.

How much do LDH do you think an Engine should carry?

[chris 31 2]

4000 feet on one engine can lay from water source to the center of town. No hydrants that are worth any thing in this town.

[petervonb 9]

In the City of Peekskill earlier this year, they had a major fire at the top of a hill and the hydrant system failed. They had to rely on a 5 inch hose lay and multiple tanker shuttles. They laid 28 lengths of 5 inch with two relay pumpers in the setup. (They probably could have used a third, or even a fourth relay pumper - the lay from source to first relay pumper was 16 lengths, all uphill, and 6 lengths between first and second relay, another six to site, where they dumped it into tanks and pumped from there.)

No way should they normally have to carry 3,000 feet of 5 inch in a hydranted city but .....

[50-65 205]

We used to carry 1000' on our engines: until the day we had a fire 1200' from the hydrant. Now we carry 1400'.

[38ff 250]

We have 2000 feet on all our engines, only about 1/4 of our area we cover has hydrants.

[antiquefirelt 994]

We carry 1300 ft. of 5" LDH on each of our engines. While most of our "in town" areas have decent hydrant spacing, other areas do not. Also, the beds are set up to be split so that dual lines may be laid if necessary. In those areas with decent hydrant density, it's not uncommon for the 2nd due engine to forward lay from a close hydrant to supply the first due engine then reverse lay to another hydrant to supply our tower.

We spent a lot of time trying to design our newest engine to have low hose bed, relatively short wheelbase, all while requiring it to hold 750 gallons of water. Basically we could have any combination of 2 of the 3, but not all 3. In the end we found that the hosebed height was not as critical a factor because the bottom of the hose bed means very little, it's where the top of the hose lay ends that we needed to be kept low. We decided to allow the hose bed to be a little higher to maintain our tank size and apparatus length, and instead mounted the ends of the hose outside the bed where they could be grabbed without leaving the ground (for most). The thought process is that when your hurrying you should have to climb up to retrieve the hose, but when your reloading you have no excuse not to take the time to conduct the lay safely. That being said, I can't understand why you'd not want to fill the hosebed as much as you could regardless of your districts make up, short of having to purchase the hose. If you have the hose, at least on an engine it has the potential to help, in the station it's just replacement or spare hose.

[antiquefirelt 994]

We used to carry 1000' on our engines: until the day we had a fire 1200' from the hydrant. Now we carry 1400'.

What'll happen the day after you have a fire 1500 ft from a hydrant? Why not just fill the bed at the outset, other than the obvious cost issue? We actually learned a newer method of laying LDH in the bed that allowed us to carry at least another 2 or 3 lengths to fit as much in without fear of it hanging up.

Edited June 7, 2013 by antiquefirelt

[Bnechis 3,961]

We actually learned a newer method of laying LDH in the bed that allowed us to carry at least another 2 or 3 lengths to fit as much in without fear of it hanging up.

Care to explain?

[antiquefirelt 994]

Care to explain?

Sure, though we may have been behind and this might be obvious to some. We lay the LDH from the rear of the bed to a point 18-24" short of the head of the bed, laying one layer the width of the bed then starting back with the second and subsequent layers. The space left open at the head of the bed is used for couplings, anytime you have a coupling you move it to that open space and short lay or create a fold to ensure the coupling doesn't have to flip, they always pull straight out. then continue the lay as normal, but always placing the couplings up front. This removes any coupling "bumps" in the lay and typically ends up with a neater lay that takes up less space. This was a real help to us as our engines all have hard deck hose bed covers and the last few lengths often were tight to the cover if couplings ended up close to each other mid-bed. I'll look for pictures that we have that show this lay.

[Bnechis 3,961]

Thanks Antique

We used that method from 1988 till just a few years ago. With our new extra low (but short) hose bed we went back to a standard flat load and found it was better as we didnt want to give up the front of the bed for just couplings.

[antiquefirelt 994]

Here's a couple of pics from other apparatus that we'd taken the idea from. I will note that we use the method as it looks but with the exception that we do not lay hose over the couplings. They show a manner that you can load when the bed is not too deep but use the same concept by placing the first tier of couplings at the head of the bed, then another tier in the low spot just back from them. Another thing this does for the load is keep couplings from having to pass each other in the bed, which can be problematic if the load is tight side to side.

[TFD141@aol.com 26]

Why purchase and spend $$ on a larger GPM pump than your initial hose can supply?

Pumper GPM is also a product of your ISO requirement for flowing water, You can always get more hose ( another engine, or mutual aid) but you can't get more GPM if the pump is too small. Our largest structure according to ISO requires over 3500 GPM, so two engines with (1500 plus 1500) is only 3000. That is one of many reasons our Tower Ladder has a 1500GPM pump as our TL is second due to gain street access so we are covered to the standards/requirements. We also could lay in another LDH from another source in case of big fire to utilize the full 1500 GPM. Additionally a two stage pump when put into pressure drops down to 1/2 its rated supply or 750GPM. If that was a 1000GPM pump it would drop down to 500GPM according to the manufacturer. 1000' of hose seems to be a good amount, and now we are ALL required by "recent" standard changes to replace our hose every ten years, and test every year, so excessive hose may be too costly as well. Of course if your district has places longer than 1000' either you plan on additional pumps or put more hose on board. We went around and included long driveways on a spreadsheet and found one single lane driveway was 1600' alone. So our plan is to wrap the tree and the second due engine lays into that tree wrapped hose..you have to plan..thats all. We also call in tankers on auto MA in the areas of long lays mainly to have water at the initial attack until the lay-in is completed which does take time. We are slowly switching to single stage pumps as the hose, pump computer and relief valves don't really allow for the full use of two stage pumps. Pressure is only is good at small fires requiring less GPM. Once big fire you probably will probably switch out of pressure side of a two stage pump.